1. Field of the Invention
The present invention relates to a database retrieval system and a computer-readable storage medium that stores a program for database retrieval, and more particularly to a database retrieval system that retrieves information from a plurality of databases and a computer-readable storage medium that stores a program for retrieving information from the databases.
2. Description of the Related Art
Many researchers of natural science usually develop their study with reference to existing data or data accumulated heretofore. Especially, in the field of chemistry, reference is often made to physical properties of an immense number of substances to create a compound having new properties. To carry out efficient research in the development of a new material, databases storing information concerning physical properties of substances are frequently used.
These databases include in-house databases developed by researchers or users of research laboratories, and databases provided by database vendors. These databases differ in contents of data stored therein. For instance, there can be a case where one database contains only values of electric conductivity and refractive indexes of substances. If the user wishes to obtain information concerning transparency and permittivity of the substances, he has to retrieve information from another database. Therefore, it is necessary for one research organization to use several databases. Further, the environment required for each search and retrieval varies from database to database, and hence the user utilizing a plurality of databases is required to selectively set up a suitable environment database by database.
To carry out retrieval of information from the different databases, query expressions are prepared for the respective databases and the retrieval of information is carried out using these expressions. Results of the retrievals obtained from all of the required databases are manually arranged in order to obtain a comprehensive listing of results of the research being performed.
However, it is an extremely time consuming operation for the user to prepare query expressions and arrange the results of the retrieval in order. Moreover, databases may not store a comprehensive set of the values of physical properties required by the user. This presents the following problems for the user:
First, when data stored on several databases is narrowed down by a query expression to obtain necessary information, data that ought to match the query expression if the data were stored in a single database can be left out of the results of the query. For example, one database contains data concerning electric conductivity and refractive indexes of substances while another database contains data concerning refractive indexes and thermal conductivity of substances. When the search is carried out by the query expression, xe2x80x9celectric conductivityxe2x80x9d AND (a logical multiplication) xe2x80x9cthermal conductivity,xe2x80x9d the query will return no data because neither database contains information fulfilling both retrieval conditions. Therefore, it is impossible to obtain information fulfilling both of the two conditions of xe2x80x9celectric conductivityxe2x80x9d and xe2x80x9cthermal conductivityxe2x80x9d from the separate databases.
Second, when the database does not store the specific data needed by the user, there is no available means to predict values for the data. For example, if data for electric conductivity of a substance is missing, it is possible to predict the electric conductivity of the substance using electric conductivity of another substance having similar physical properties. However, information documenting the similarities between the substances that can be used in making this kind of prediction is so diverse that it is difficult for individual users to determine the required similarities.
It is a first object of the invention to provide a database retrieval system that solves the problems encountered when a plurality of databases are used in combination.
It is a second object of the invention to provide a database retrieval system that is capable of providing data for reference such that missing data can be predicted.
It is a third object of the invention to provide a computer-readable storage medium storing a database retrieval program that is capable of solving the problems encountered when a plurality of databases are used in combination.
It is a fourth object of the invention to provide a computer-readable storage medium storing a database retrieval program that is capable of providing data for reference such that missing data can be predicted.
To attain the first object, according to a first aspect of the invention, there is provided a database retrieval system for carrying out information retrieval from a plurality of databases, comprising integrated information retrieval means responsive to retrieval conditions input, for integrating data separately added to identical records in a plurality of databases and retrieving records matching the retrieval conditions based on integrated information of the data.
To attain the second object, according to a second aspect of the invention, there is provided a database retrieval system for carrying out information retrieval from a database, comprising systematic information retrieval means responsive to a systematic information retrieval command in which a particular record is designated, for retrieving, from the database, other records systematically close to the designated particular record.
To attain the third object, according to a third aspect of the invention, there is provided a computer-readable storage medium storing a program for retrieving information from a plurality of databases, the program controlling a computer to function as integrated information retrieval means responsive to retrieval conditions input, for integrating data separately added to identical records in a plurality of databases and retrieving records matching the retrieval conditions based on integrated information of the data.
To attain the fourth object, according to a fourth aspect of the invention, there is provided a computer-readable storage medium storing a program for retrieving information from a database, the program controlling a computer to function as systematic information retrieval means responsive to a systematic information retrieval command in which a particular record is designated, for retrieving, from the database, other records systematically close to the designated particular record.
The above and other objects, features and advantages of the present invention will become apparent from the following description when taken in conjunction with the accompanying drawings which illustrate a preferred embodiment of the present invention by way of example.